A policeman has been wounded in a stabbing attack in front of the main police station in the Belgian capital of Brussels.

The attacker stabbed the officer outside the police station at 5:30 am (0430 GMT) on Tuesday, police spokeswoman Ilse van de Keere said.

"A police officer was stabbed and slightly wounded" and transferred to the hospital, she told AFP.

The attacker was shot and injured by another officer.

"His (the wounded officerís) colleagues retaliated by firing shots at the attacker who was subdued," the spokeswoman said, explaining that the assailant had not sustained life-threatening injuries.

A local newspaper said the attack was apparently carried out by Takfiri militants, though police said the motive was unclear and stressed that an investigation was underway.

The attack took place during a two-day visit to Belgium by French President Emmanuel Macron.

Over the past years, Belgium has suffered a series of terrorist attacks, mainly by the recruits of Daesh, a Takfiri terrorist group that is now almost purged from its former bastions in Iraq and Syria. The Western European country remains on high alert since a Daesh cell based in Brussels carried out massive attacks in Paris in November 2015 and killed 130 people in a matter of a night. The same terror cell was behind attacks in Brussels a year later that killed 32 people.